1. Field of the Invention
The invention relates generally to expansion joint assemblies for interior and exterior building voids and, more particularly, but not by way of limitation, it relates to an improved form of expansion joint assembly for usage in expansion voids of relatively wide variance spacing that utilizes a novel centering structure.
2. Description of the Prior Art
The prior art includes numerous types of expansion joint assemblies for both interior and exterior application which include various kinds of expansion plate in combination with diverse types of support and centering structure. A representative type of expansion joint assembly with centering bar is represented by U.S. Pat. No. 3,183,626 in the name of Schmitt, a type of assembly that has enjoyed popular application for a long number of years. The Schmitt structure utilizes a centering bar that is centrally, pivotally fixed to the expansion assembly while having the ends ball-supported in adjacent slideways on opposite sides of the expansion void. U.S. Pat. No. 3,797,952 discloses a roadway expansion joint that utilizes a series of hinged lazy tong assemblies, pivotally fixed on a four-corner scheme, to support individual intermediate bars movably thereby to provide an expandable roadway support. In this case, each lazy tong upper hinge also supports an elongated intermediate bar which serves as traffic support across the expansion void.
U.S. Pat. No. 3,648,423 in the name of Cole discloses another form of expansion joint assembly, a flush mount device, which includes a lazy tong centering arrangement in addition to a spring retaining member and resilient seating structure. The expansion joint assembly, as proposed for adjoining panels of floor, wall, ceiling or the like, forms an elongated assembly having a plurality of spaced lazy tong centering linkages intersticed with a plurality of leaf spring devices for maintaining the expansion joint assembly in secure flush mount within said expanding surfaces. This structure is designed for recessed mount to provide smooth or generally planar exterior surface, and as such it is limited to much more narrow width expansion voids.